[Corvettaholic]

What unit is kinetic energy measured in? Newtons? Also, if I know the mass of the object, and its velocity, is that all I need to determine kinetic energy? I'm thinking on a real basic level, nothing too fancy here. Lets say the mass is 10g, and the velocity is 20 meters/second... what formula should I use to figure this out?

[Mitch]

All energy is measured in Joules.      

The formula is (0.5)mv².

Where m is the mass in units of kilograms. And v is in units of meters/second.

[Donaldson Tan]

all energy is measure is joules.

1J = 1N x 1m = (1kg x 1m/s²) x 1m = 1 kg.m²/s²

[arnyk]

Lol, I'm going to be the third person to say the exact same thing again.

The SI unit for energy is the joule (J).  When calculating always remember to use SI units consistently:

Energy = J
Speed = m/s
Force = N

General equation for E_k  = mv² / 2

Derivation...umm...

E = Fd
(F = ma)
E = mad
(d = at² / 2 ) non-uniform
E = ma²t² / 2
( v = at)
E_k = mv² / 2

Looks about right, I'm waiting for my high school physics teacher to rip that apart.

[Corvettaholic]

Thanks for the help guys  

So I found the ball bearing I want to launch, and it weights 1kg. After some googling, a 9mm bullet has about 940 joules of energy when it hits something. So if I want to find out how much velocity I need:

540 = (0.5) * (1) * (v)²

1080 = v²

32.8 = v

So 32.8 meters per second is the velocity I need. I wonder how fast that really is?

[Borek]

So 32.8 meters per second is the velocity I need. I wonder how fast that really is?

About 60 mph. But it seems to me that you have mistyped 540 instead of 940 so you need about 43 m/s which is 100 mph. Which is nothing for Corvette